Lunar Module Eagle is pictured in lunar orbit after undocking and prior to landing on the Moon on Sunday, July 20, 1969. NASA/CNP/Newscom/FILE

United States President Richard M. Nixon was in the central Pacific recovery area to welcome the Apollo 11 astronauts aboard the U.S.S. Hornet, the primary recovery ship for the Apollo 11 mission. Already confined to the Mobile Quarantine Facility are (left to right) Neil A. Armstrong, commander; Michael Collins, command module pilot; and Edwin E. Aldrin Jr., lunar module pilot. Apollo 11 splashed down at 11:49 a.m., July 24, 1969, about 812 nautical miles southwest of Hawaii and only 12 nautical miles from the U.S.S. Hornet. The three crew men would remain in the MQF until they arrived at the Manned Spacecraft Center's Lunar Receiving Laboratory. NASA/CNP/Newscom/FILE

'Buzz' Aldrin is seen during the Apollo 11 extravehicular activity on the surface of the Moon on July 20, 1969. During the eight-day space mission, Armstrong and Aldrin explored the Moon's surface and brought back rock samples for scientists to study. NASA/UPI/Newscom/FILE

US Navy pararescueman Lieutenant Clancey Hatleberg disinfects the Apollo 11 astronauts in a life raft during recovery operations on July 24, 1969 upon successful completion of their lunar landing mission. As an estimated 500 million people around the world waited with bated breath crowded around fuzzy television screens and radios, Neil Armstrong stepped down the lunar module's ladder and onto the lunar surface on July 20, 1969. AFP/NASA/FILE

Vice President Spiro Agnew and former President Lyndon B. Johnson (c.) view the liftoff of Apollo 11 from pad 39A at Kennedy Space Center, Florida at 9:32 am EDT on July 16, 1969. NASA/UPI/Newscom/FILE

This photo, taken July 16, 1969, shows Apollo 11 crew members, led by Neil Armstrong, walking to the van that will take them to the rocket for the launch. Newscom/FILE

New York City welcomes the three Apollo 11 astronauts in a showering of ticker tape down Broadway and Park Avenue, in a parade termed at the time as the largest in the city's history on August 13, 1969. NASA/CNP/Newscom/FILE

United States President Richard M. Nixon and Dr. Thomas O. Paine, NASA Administrator, watch Apollo 11 astronauts walk from the recovery helicopter to the Mobile Quarantine Facility aboard the U.S.S. Hornet on July 24, 1969. The President later congratulated the astronauts by microphone, speaking through a window of the quarantine trailer. NASA/CNP/Newscom/FILE

'Buzz' Aldrin is photographed during the Apollo 11 extravehicular activity (EVA) on the lunar surface Sunday, July 20, 1969. In the right background is the Lunar Module 'Eagle.' On Aldrin's right is the Solar Wind Composition experiment already deployed. This photograph was taken by Neil A. Armstrong with a 70mm lunar surface camera. NASA/CNP/Newscom/FILE

A technician works atop the white room through which the Apollo astronauts will enter their spacecraft, which is stacked at the top of a Saturn V rocket on July 3, 1969. NASA/CNP/Newscom/FILE

A view of the Earth appears over the Lunar horizon as the Apollo 11 Command Module comes into view of the Moon before Astronauts Neil Armstrong and Edwin Aldrin Jr. leave in the Lunar Module, 'Eagle'. NASA/CNP/Newscom/FILE